Process for producing sheet glass



Aug. 16, 1932. c. w. SWOPE' PROCESS FOR PRODUCING SHEET GLASS Filed June '7. 19:50

2 Sheets-Sheet l Char/e5 (0. 6400 06.

C. W. SWOPE Aug. 16, 1932.

PROCESS FOR PRODUCING SHEET GLASS Filed June '7. 1930 2 Sheets-Sheet 2 mu-mum! C her/es a). wope. M y

Patented Aug. 16, 1932 UNITED STATES PATENT? OFFICE CHARLES W. SWOPE, OF TOLEDO, OHIO, ASSIGNOR TO LIIBBEY-OWENS-FORD GLASS COM-- PANY, OF TOLEDO, OHIO, A CORPORATION OF OHIO PROCESS FOR PRODUCING SHEET GLASS Application filed June 7,

The present invention relates to a process for forming and annealing sheet or plate glass.

According to one process of manufacturing sheet glass, a plurality of successive sheets or plates of glass are intermittently rolled at predetermined intervals from a series of charges or masses of molten glass, the molten glass being preferably melted and refined within suitablereceptaclesor pots and poured therefrom onto a receiver from where it is moved to and passed between a pair of forming rolls which function to reduce the glass to a sheet of substantially predetermined and uniform thickness. In such process, it is desirable from both the'standpoint of quality and production, that the glass sheets be formed at a relatively high rate of speed, after which the speed of travel thereof be materially reduced so that the sheets will be permitted to move at a relatively slower speed during annealing in order that the annealing apparatus need not be of an undesirable length. Also, in such process, it is desirable that the glass sheet'be carried forwardly as it is formed at a relatively high rate of speed until it has become sufliciently set to support its own weight in order to prevent sagging of said sheet between the spaced rolls commonly employed for supporting the same. The carrying of the sheet forwardly at a high rate ofspeed until it becomes set requires a the use of a conveying and/or annealing apparatus of considerable length, even though the time required in cooling be only a matter of a few minutes. 7

One of the objects, therefore, of this invention is the provision of a process whereby a mass of molten glass may be rapidly reduced tosheet form and the said sheet subsequently anneal-ed while traveling at a relatively slower rate of speed.

Another object of the invention is the pro vision of a process wherein the speed of forward travel of the sheet may be reduced from 1930. Serial No. 459,645.

its relatively high forming speed to a relatively slower annealing speed easily and conveniently, while giving maximum support to the sheet to prevent sagging thereof.

A further object of the invention is the provision of a process wherein the sheet can be carried forwardly over a series of transverse supports at a relatively high rate of speed to prevent sagging thereof with a rela tively slow forward movement in order that a rglatively short conveying means may be use A further object of the invention is the provision of a process wherein the sheet is carried forwardly upon a series of supporting rolls movable bodily beneath the sheet prefer: ably in a direction opposite to that of the travel thereof so as to more rapidly shift the lines of support from one position to another beneath the sheet, thereby leaving no portion of the sheet unsupported for any material interval of time and giving it substantially no opportunity to sag, each of the sheet supporting rolls being simultaneously rotated about its own axis in the same direction as the movement of the sheet. v

Other objects and advantages of the invention will become more apparent during the course of the following description when taken in connection with the accompanying drawings.

In the drawings forming a part of this application and wherein like numerals are employed to designate like parts throughout the same, 3

Fig. 1 is a vertical longitudinal section through apparatus constructed in accordance with the present invention,

Fig.2 is a planview thereof,

Fig. 3 is a side elevation of the forward portion of the annealing leer, showing the means for mounting and driving a part of the sheet conveying mechanism, and

I Ch Flg. ais a section taken substantially on I line H of Fig. 3.

Referring to the drawings, 5 designates a receiver or supportadapted to receive thereupon a mass or charge of molten glass 6 which is to be reduced to sheet form, said glass being supplied to the receiver from a pot or receptacle 7. Associated with one end'of the receiver are the sheet forming rolls 8 and 9 arranged relative to one another to create a sheet forming pass therebetween through which the molten glass is moved and reduced to a sheet 10 of substantially predetermined and uniform thickness. As pointedout above, it is desirable that the glass sheet be formed at a relatively high rate of speed and the rolls 8 and 9 are consequently rotated in a manner to rapidly reduce the mass of molten glass 6 to sheet form.

As the glass sheet 10 leaves the forming rolls, it passes downwardly over an inclined apron or slab 11 and is subsequently deflected into the horizontal plane and carried forwardly into and through an annealing leer designatedin its entirety by the numeral 12. Arranged within the leer are a series of horizontally aligned rolls 13 adapted to support and convey the glass sheet therethrough at a constant relatively slow speed, said rolls being driven'from a motor 14 through suitable reduction gearing 15 and a sprocket chain 16 trained about sprockets (not shown) carried at the ends of said rolls. Of course, any other suitable type of driving means may be employed without departing from the spirit of the invention.

The leer rolls 13 are adapted to be driven at a constant relatively slow annealing speed which is materially less than the peripheral speed of the forming rolls 8 and 9 during the formation of the sheet. For example, the leer rolls may be driven at from two to fif- .teen feet per minute while the sheet is formed at the vrate of from forty to sixty feet per minute. Consequently, some means must necessarily be provided for effecting a reduction in the forward speed of travel of the sheet after it has been formed and prior to its being delivered or passed onto the leer rolls 13. In order to accomplish this and the other sitioned within the forward end of the leer objects of the present invention, there is po- 12 between the forming mechanism andleer rolls 13 a pair of endless conveyors designated in their entirety by the numerals 17 and 18. Although two conveyors have been here shown, it is to be understood that one or-any number may be .used as preferred.

' Also since each conveybr is of the same construction, a description of only: one will be belt being trained about the horizontally spaced drums20 and 21 mounted upon shafts 22 and 23 respectively at each end of which is' carried a sprocket 24. Each roll 19 is carried upon a shaft 25 which projects at opposite ends through slots 26 formed in the side walls of the leer. The shaft 25 of each roll links, said chains being trained about the sprockets 24. To rotate the chains in unison, either shaft 22 or 23 may be positively driven from a motor 31 through suitable reduction gearing located in casing 32. The adjacent overlapping ends of the links forming the chains 29 and 30 are provided with aligned openings through which the projectin end portions of roll shafts 25 extend, as s own in Fig. 4, the links being held upon the shafts bynuts 33. In other words, the rolls 19 are connected in endless belt formation by the links which connect? the adjacent roll shafts 25. Upon rotation of sprockets 24to drive chains 29 and 30, the rolls 19 will be carried bodily along rails 28 with respect to the sheet 10 resting thereupon. During such travel, the roll shafts 25 are free to rotate within bearings 27 and, in order to also permit free rotation thereof, the said shafts are loosely mounted within bushings 34 arranged within the aligned, openings through the chain links. I

For the purpose of rotating each of the rolls 19 about its own individual axis in the direction of movement of the sheet while said rolls are being bodily moved in the opposite direction, there is niounted upon one end of through suitable reduction gearing located in casing 40. Upon rotation of sprockets 37, the endless chain 36 will-engage sprockets 35 and rotate therolls about their individual axes in a direction opposite to the direction in which they-are being carried bodily. F or the purpose of maintaining the chain 36 in engagement with sprockets 35, there may be provided a longitudinally extending plate or the like 41 carried by brackets 42, said late holding the lower horizontal run of the c ain downwardly in engagement with said sprockets.

In carrying the invention into practice,

and by way of illustration onl let us assume that a glass sheet #10, sixty feet in length, is adapted to be formed at approximately sixty feet per minute and annealed while traveling at the rate of ten feet per minute. In such case, the forming rolls 8 and 9 will be driven in such a manner that they will have a. peripheral speed of sixty feet per minute, and the leer rolls 13 driven so that they will have a peripheral speed of ten feet per minute. Duringthe formation of the sheet, it is preferredthat the chains 29 and 30 be driven so as to move the rolls 19 bodily at fifty feet per minute in a direction opposite to the direction of movement of the sheet and that the sprocket chain 36 be simultaneously driven in the opposite di- 5 .rection at sixty feet per minute. Thus, since the rolls 19 are being carried bodily in one direction at fifty feet per minute and the chain 36 simultaneously moving in the opposite direction at sixty feet per minute, 20 the said rolls will be driven about their individual axes at the rate of 110 feet per minute while the forward travel of the sheet over the rolls will be but sixty feet per minute or, in other words, equal to the speed of' formation of the sheet. After the sheet has been formed and is completely received upon the conveyor 17 the speed of travel of the sprocket chain 36 is reduced to ten feet per minute which will effect a reduction in the so forward speed of travel of the sheet to ten feet per minute so that the sheet will be discharged from the conveyor onto the lear rolls 13 at annealing speed; Of course, the speeds above mentioned are merely given by way of example only since any relative speeds may be used. In addition, the reduction in the speed of travel of the sheet can be effected in different ways such as by varying the speed of the chain 36 as above described,

4a or in maintaining this speed constant and varying the speed of the chains 29 and 30,

or by varying both. However, the above method of operation is desirable for the reason that at no time will it be necessary to completely stop either the bodily movement of the conveyor rolls 19 or the rotation thereof.

From the above, it will be apparent that there has not only been provided a process and apparatus whereby successive sheets of glass may be formed at a relatively high rate of speed and subsequently annealed while traveling at a relatively slower speed,

but wherein this can be accomplished in an easy andconvenient manner while, at the same time, giving maximum support to the sheet to prevent sagging thereof. Thus, the rolls 19 can be moved bodily so that no portion of the glass sheet will remain unsupported long enough to give it time to sag between the rolls. In other words, the lines of support formed by the upper surfaces of the series of rolls are being shifted from place to place so rapidly that practically a continuous support is provided for the lower surfaces of the sheet. In addition, due to the simultaneous rotation of the rolls about their individual axes, the said rolls will have .is to be taken as the preferred embodiment of the same, and thatvarious changes in the shape, size and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the subjoined claims. 1

I claim:

1. The process of producing sheet or plate glass,'which consists in intermittently forming successive sheets of glass by a rolling operation and at a relatively high rate of speed, receiving and carrying each sheet forwardly as it is formed upon a series of surfaces bodily movable with respect to the sheet and in a direction opposite to the forward movement thereof, in reducing the speed of forward travel of the sheet while upon said surfaces and-while maintaining the said bodily move- 7 ment of the surfaces relative to the sheet, and in then passing the sheet at such reduced speed into and through an annealing zone.

2. The process of producing sheet or plate glass, which consists in intermittently forming successive sheets of glass by a rolling operation and at a relatively high rate of speed, receiving and carrying each sheet forwardly as it is formed upon a series of continuously revolving surfaces having rolling contact with the sheet and being bodily movable relative thereto in a direction opposite to the forward movement thereof, in reducing the forward speed of travel of the sheet while upon said surfaces and while maintaining the said bodily movement of the surfaces relative to the sheet, and in then passing the sheet at such reduced speed into and through an annealing zone.

3. The process of producing sheet or plate glass, which consists in intermittently forming successive sheets of glass by a rolling operation and at a relatively high. rate of speed, receiving and carrying each sheet forwardly as it is formed'and at a speed substantially equal to its speed of formation upon a series of surfaces bodily movable with respect to the sheet so that the said sheet travels. over said surfaces at a speed relatively greater than its speed of formation, in reducing the forward speed 'of travel of the sheet while upon said surfaces and maintaining a relatively greater speed of movement of the sheet over said surfaces, and in then.- passing the sheet at such reduced speed into and throughan annealing zone.

4. The process of producmg sheet or plate glass, which consists in intermittently form-- ing successive sheets of glass by a rolling opglass, which consists in intermittently forming successive sheets of glass by a rolling operation and at a relatively high rate of speed,

-. and through an annealingzone.

5. The process of producing sheet or plate eration and ata relatively high rate of speed, receiving and carrying each sheet forwardly as it is formed and at a speed substantially equal to its speed of formation upon a series of spaced transverse supports bodily movable relatiw e to the sheet and in a direction opposite to the forward movement thereof so that the said sheet travels over the supports at a speed relatively reater than its speed of formation, .in reducing the forward speed of travel of the sheet while .up'on the supports and maintaining a relatively greater speed of movement of the sheet over said supports,

and in then passing the sheet at such reduced 7 speed into and through an annealing zone.

:tially equal to the speed 6. The process of producing sheet or plate glass, which consists in intermittently forming successive sheets of glass by a rolling operation and at a relatively high rate of speed, receiving and carrying each sheet forwardly asit isformed and at. a speed substantially equal to itsspeed of formation upon a series of'spaced transverse supports bodily movable relativeto the'she'et and in a direction opposite to the forward movementthereof'so that the saidsheet travels over the supports at a speed relatively greater than its speed of formation, in reducing the forward speed of travel of the sheet while upon the supports and maintaining a relatively'greaterspeed of movement of the sheet over said supports, in transferring the sheet at such reduced speed onto a second series of spaced transverse supports while maintaining the relatively. high. speed of travel of the sheet over said first mentioned transverse supports until the sheet is entirely received upon said second series of supports, and in conveying the sheet upon the second series of supports through an annealing zone.

7. ,The process of producing sheet or plate glass,-which consists in intermittently forming successive sheets of glass by a rolling operation and at a relatively high rate of speed, receiving each sheet as it is formed and carrying it forwardly at a'speedsubstanof formation thereof,

upon a series of continuously revolving surfaces bodily movable with respect to the sheet and in a direction opposite to the forward movement thereof so that the said sheet travels over said surfaces at a speed relatively greater than its speed of formation, then reducing the forward speed of travel of the sheet, while upon said surfaces and while maintaining a substantially greater speed of movement of the sheet over said surfaces until the sheet has become substantially set, and in then passing the sheet at such reduced speed from said surfaces into an annealing zone.

8. The process of producing sheetor plate glass, which consists in intermittently form ing successive sheets of glass by a rolling operation and at a relatively high rate of speed, receiving and carrying each sheet forwardly as it is formed upon a series of con tinuously revolving I supporting surfaces bodily movable with respect to the sheet and distance, after which its speed of forward.

trayel is reduced to a relatively slower speed, WhlCl'l consists in receiving and carrying each sheet forwardly as it is formed upon a series .of surfaces revolving in the same direction as (the forward movement of the sheet and being simultaneously bodily movable with respect to the sheet and in a direction opposite to the forward movement thereof so that the travel of the sheet over the surfaces is relatively greater than its forward movement, in reducing the speed of forward travel of the sheet while upon said surfaces, and concurrently'maintaining the said bodily movement of the surfaces relative'to the sheet, and in then passing the sheet at such reduced speed from said surfaces into an annealing zone. 10. The process of producing sheet or plate glass, wherein the sheet is formed at a relatively high rate of speed. carried forwardly at its speed of formation for a predetermined distance, after which its speed' of. forward travel is reduced to a relatively slower speed, which consists in receiving and carrying each sheet forwardly as it is formed'upon a series of surfaces revolving in the same direction as the ,forward movement of the sheet and being simultaneously bodily movable with respectto the sheet andin a direction opposite to theforward movement thereof so that the travel ofnthe sheet over the surfaces is relatively greater than its forward movement, in reducing the speed of forward travel of the sheet while upon said surfaces by varying the v ratio of the speed between the revolving movement of the surfaces and the bodily movement thereof while maintaining the said bodily movement of the surfaces relative to the sheet, and in thenpassing the sheet at such reduced speed from said surfaces into an annealing zone.

Si ed at Toledo, in the county of Lucas and tate of Ohio, this 5th day of June, 1930.

CHARLES W. SWOPE. 

